More in Crop Chemicals

Weed resistance is increasing “at an alarming rate,” and with no new herbicide sites of action becoming available in the immediate future, “we need to follow stewardship programs to the letter to preserve the herbicide products we have,” warns Michael Owen, Iowa State University Extension weed specialist. Common waterhemp, marestail (horseweed) and giant ragweed are likely to be the biggest weed challenges for Corn Belt farmers in 2013, and Palmer amaranth will be the next big weed threat, Owen says....More

New herbicide offerings for 2013 will allow growers to follow the resistance management advice of leading weed scientists – always use a soil-applied pre-emergence herbicide and employ multiple sites of herbicide activity. See mode of action chart (pdf).

Colony Collapse Disorder (CCD) continues to keep honeybees in the headlines as beekeepers lose on average one-third of their hives annually. But CCD is not the only problem that affects bees. Bee populations in general, including bumblebees and ground-nesting solitary bees, are declining....More

Biologically based crop inputs are moving from the orchards and cabbage patch to corn and soybean fields. A combination of higher value commodity crops, synergies between biologicals and synthetic chemical controls, new research tools and major corporate investments are driving the trend....More

If you’ve gotten into the habit of using foliar fungicides in corn simply to boost plant health and yields, you may want to reconsider. Research by Midwest university crop specialists confirms disease risk conditions should be the overriding reason to evaluate the costs and benefits associated with any corn fungicide applications....More

In 2012, Greg Kerber attacked the weeds in his no-till soybean fields with six herbicide modes of action – including three effective pre-emergence herbicides. An early April burndown included full rates of 2, 4-D and glyphosate plus soil-residual products Prowl and Sonic, followed by an early postemergence application of Liberty. Sites of action: 2, 3, 4, 9, 10 and 14....More

This summer's lack of rain has translated into the potential for summer-applied herbicides to carry over into winter wheat or even spring-planted corn and soybean crops – something growers need to be monitoring, say Bill Johnson and Travis Legleiter, Purdue Extension weed scientists. In a normal year, soil moisture helps dissipate herbicide soil concentrations, but in a drought year, the lack of moisture slows that process. Some herbicides might carry over and exceed the labeled crop rotation restrictions meant to prevent injury to the next crop....More

The growing season is finished, but the drought continues to affect soil. There are concerns from farmers about herbicide carryover into 2013. Brent Wilson, DuPont Pioneer, and Jeff Carpenter, DuPont, talk about the potential for herbicide carryover and how to manage that carryover. The keys to management are to consider late POST-applications and understand which active ingredients were applied....More

Dow AgroSciences and the Save Our Crops Coalition (SOCC) have been engaged in discussions to resolve SOCC concerns regarding the potential for herbicide injury to non-target plants after the introduction of Dow AgroSciences’ new 2,4-D tolerant crops. Dow AgroSciences and SOCC have successfully concluded those discussions....More

If drought hit your fields, no doubt you want to put this season in the rearview mirror fast and plan for a more normal crop in 2013. But before you begin to lock in whatever good seed numbers might be available during a coming year of short supply, take a detailed look at each field's 2012 herbicide and fertilizer applications....More

While the stomach-churning drought of all droughts gets 24/7 news coverage, our cover story focus for August emphasizes an even larger problem that will remain in your fields well beyond this one crop cycle. And you can't buy insurance for it. The southern Minnesota field on the cover is being overrun by resistant giant ragweed, spread via combine and pollen. The glyphosate molecule will no longer control this prolific weed seed producer – similar to waterhemp and its pigweed cousin Palmer amaranth....More

One reason glyphosate-resistant weeds are multiplying is lack of early detection. Because glyphosate has been so effective, busy farmers often skimp on scouting after spraying, says Jeff Stachler, Extension weed scientist at North Dakota State University and the University of Minnesota. As a consequence, “we’re not detecting weed changes from year to year.”...More

Over the past few weeks, the primary question I have been asked is whether foliar fungicides still provide a benefit to drought-stressed crops. In issue 12 (June 22), I summarized corn foliar fungicide research trials conducted from 2008 to 2011. The greatest yield response and the greatest likelihood of a profitable fungicide application were observed where disease pressure was the highest. Foliar fungal disease pressure will be low in water-stressed fields, so the likelihood that fungicide application will be profitable is low....More

Scientists searching for clues to understand how superweeds obtain resistance to the popular herbicide glyphosate may have been missing a critical piece of information, a Purdue University study shows. Glyphosate, the active ingredient in the weed killer sold under the name RoundUp, is the most widely used herbicide in the United States, but some plants have grown resistant to it. This has caused farmers to turn to additional herbicides....More

It has been hot and dry for most of the corn-growing season so far. These conditions are highly unfavorable for foliar diseases to develop in field corn, yet several producers have expressed interest in applying foliar fungicides. Gray leaf spot (GLS), the number one foliar disease of corn in Ohio, develops best at temperatures between 70° and 90° F, especially when conditions are consistently wet and humid....More

Ford Baldwin of Practical Weed Consultants, LLC, in Austin, Ark., says Midwest growers are just two years away from losing glyphosate as an effective herbicide – just as Southern farmers already have. "It's now a grass herbicide in the South," said Baldwin, who was speaking on "Weed Resistance 2.0" during Beck's Hybrid Media Day in Atlanta, IN. "We can no longer build a herbicide program around it. It's not just a broadleaf weed (herbicide) anymore.”...More

Continued dry weather in areas of Ohio will affect the activity of postemergence herbicides, and this can mean a reduction in weed control compared with years when soil moisture is adequate. A couple of decades of accumulated knowledge on dry weather and postemergence herbicide applications allows us to offer the following management suggestions, although none of these are probably hard and fast rules....More

The ongoing evolution of herbicide-resistant weeds is a source of worry in Illinois, says University of Illinois (U of I) Professor of Molecular Weed Science Patrick Tranel. He and research assistant Nick Hausman will be making a presentation on this topic during the 56th annual Agronomy Day at the U of I on Aug. 16....More

Farming is a challenging business, and among those challenges is chemical use. Nevin McDougall, senior VP, North America crop protection, BASF, talks about some of the challenges facing farmers today, including weed management and fungicide use and how BASF is doing its best to help farmers maintain a sustainable use of such chemicals....More

The corn and soybean crops are off to a nice start in southern Minnesota and northern Iowa, says Kent Thiesse, former Extension educator and vice president of MinnStar Bank in Lake Crystal, MN. He notes that drought-like conditions have been overcome by some nice rainfall in May, which included some storms. Herbicide application has been a challenge due to wind and rain, Thiesse says....More

Across southern Minnesota and northern Iowa, nearly all the intended corn is planted, and over 90% of the soybeans were planted as of May 18. Most of the corn and many of the soybeans that are planted in this region have emerged, and stands look fairly good....More

The eastern Corn Belt's early corn crop has started to – and so have the weeds. So now is the time for growers to consider postemergence herbicide applications, says Travis Legleiter, a Purdue Extension weed specialist. In the northern part of the Corn Belt, some of the crop is as far along as the V3, or third leaf, growth stage. Development is even further along in some fields in the southern part of the region. That means corn farmers need to prepare to apply the right postemergence herbicide at the right time, likely within the next few weeks....More

During the past week, the number of observations and inquiries related to corn injury from herbicides increased, says University of Illinois Associate Professor of Weed Science Aaron Hager. Instances of corn injury appear to be fairly widespread across the state. Direct application of postemergence herbicides and persistence of herbicides applied last season appear to be responsible for much of the injury....More